The present invention relates to a waterproof structure for a fan motor installed in vehicles such as automobiles and trucks.
Conventional fan motors for cooling vehicle capacitors and similar components are configured so that a fan boss portion is mounted on the vertical motor shaft projecting from the lower surface of a motor yoke. Such fan motors are fitted to, for example, the lower portion of a vehicle.
However, since a water-barrier for protecting the complete underside of a vehicle is normally not provided, the motor shaft of a fan motor is sometimes directly splashed with water when the lower portion of the vehicle body is splashed with water during a rain or while the vehicle is being washed. It is therefore necessary to take measures to waterproof the fan motor. In a case of a fan motor having a vertical motor, as described above, when the fan boss portion is formed into a bottomed cylindrical shape having an open upper portion, a bottom opposite to the lower surface of the motor yoke and an outer cylinder opposite to the outer periphery of the motor yoke to protect the motor from being directly splashed by water splashing the lower portion of the vehicle, the water which enters the fan boss portion cannot be easily discharged to the outside, and thus may enter the fan motor. To correct this problem it is necessary to take measures that effectively protect the fan motor from the retained water.